Lubricating oil composition



United States Patent 3,036,003 LUBRICATHNG OIL CGMPGSITION Joseph Arthur Verdoi, Dalton, llL, assignor, by mesne assignments, to Sinclair Research, Inc., New York, N.Y., a corporation of Delaware No Drawing. Filed Aug. 7, 1957, Ser. No. 676,719 7 Claims. (Cl. 252-314) This invention relates to the improvement of mineral oil compositions, and more particularly to the improvement of lubricating oils containing basic salts of oilsoluble sulfonates by the addition thereto of an effective inhibitor-detergent type additive agent.

A variety of additive agents have been designed for the addition to lubricating oils whereby one or more properties of the oil would be improved. For example, metallic detergents in lubricating oils adapted for use in internal combustion engineshave been found to improve the vehicle operation by preventing or retarding corrosion, piston ring sticking, cylinder wear, and carbon and varnish formation. Among the detergent-dispersant typeadditives used for this purpose are the so-called basic salts or soaps of oil-soluble petroleum sulfonic acids. These basic compounds are well-known materials and are preparedby neutralizing the acid with an excess of neutralizing agent which is in the form of the oxide, hydroxide or carbonate of the desired metal, so as to obtain a product which contains an amount of metal in excess of that theoretically required to replace the acidic hydrogens of the acid. Such detergents have been used with much success in lubricating oils for internal combustion engines. However, in lubricating oils containing other additive agents, for example, anti-oxidants such as alkyl phenol sulfides and their metal salts, these basic detergent materials often have the objectionable feature of being fairly corrosive toward metals and alloys which are widely used as bearing metals.

In accordance with this invention I have found that if a condensation product of an alkylene polyamine, an aldehyde and substituted phenol, or an alkaline earth metal salt thereof, is added to a mineral lubricating oil which contains a basic alkaline earth metal salt of an oilsoluble petroleum sulfonate, the combination of additives will efi'ectively reduce the tendency of such oils to undergo oxidation, formation of gums, sludges, and other deterioration which occurs when the oil is used in internal combustion engines. When the alkaline earth metal salts of the condensation product are used in conjunction with the oil-soluble sulfonates good' performance is obtained with respect to engine cleanliness and bearing corrosion.

The metallic derivatives have been found especially suited as detergent-inhibitors and can be used in amounts appreciably less than other additives known in the prior art in order to obtain a desired level of performance. As ashless detergent-inhibitors, the non-metallic condensation products do not have the objectionable feature of leaving a deposit or ash. in internal combustion engines and are highly desirable for inhibiting oxidation.

In order to obtain the oil-compatible, i.e. soluble, dispersible or miscible without continuing agitation, condensation products used in accordance with this invention, an alkylene polyamine, formaldehyde and substi-- tuted phenol are reacted together at an elevated'tempera- "ice ture, such as a temperature in the range of to 350 F., in the presence or absence of a solvent. The reactants are employed in a ratio of at least about 0.5 mole of each of phenol and aldehyde for every basic nitrogen atom present in the alkylene polyamine, with the upper limit being about 2 moles of phenol and aldehyde for each nitrogen atom in the amine. T-he condensation products are essentially linear and thus are not condensed to an infusible and insoluble stage such as occurs in the usual phenol-formaldehyde condensation reactions, but have reactive phenolic hydroxy groups which remain unsubstituted or which have hydroxyl hydrogens replaced with an alkaline earth metal. It is believed that the molecular weight of the product is in the range of 500 to 5000. The desired metal of the alkaline earth group ispreferably introduced by reaction of its oxide or hydroxide with the condensation product.

As indicated above, the reactants are maintained in a ratio of at least about 0.5 mole of phenol and aldehyde for every basic nitrogen atom present in the amine. In this manner the products thus obtained. have been found to exhibit good oil solubility, wide molecular Weight dis tribution and varying amounts of nitrogen. As an example, the condensation of 3 moles of p-t-octylphenol and formaldehyde with one mole of diethylenetriamine affords a product which may be illustrated as:

R OH R in which R is the alkyl group of the phenol. However, when the reaction is carried out using a ratio of 2 moles of the same aldehyde and phenol per mole of amine, a product of lower molecular weight and higher nitrogen content is formed, which is represented as:

in which R is the alkyl group of the phenol. Similarly, when tetraethylenepentamine is used as the alkylenepolyamine source in the above condensation reaction, a series of high molecular weight'condensation products are obtained. Thus, a condensation product formed from the reaction of 4 molestof octylphenol and'formaldethyde per mole of tetraethylenepentarnine affords a product comprised of several compounds the major portion of which are shown below:

recovered as a mineral oil concentrate.

(1m -OH I -OH OH I OH por ng Since the ratio of reactants employed in the above condensation were such that one secondary nitrogen atom would remain unsubstituted, a mixture of products could not be precluded and it is believed that the above formulations predominate although positioned isomers other than those shown are also possible. Similarly, when the same reaction is carried out using a higher ratio of reactants, a condensation product higher in molecular weight and lower in nitrogen content is obtained. Thus, the condensation product obtained by reacting 5 moles of octylphenol and formaldehyde with one mole of tetraethylenepentamine is illustrated by the probable structure shown below:

hm dm 7 v I O-on alkylated monohydric phenols having at least one alkyl group of sufiicient length to impart oil-solubility to the condensation products. Such phenols are further characterized as having at least one ortho or para position which is available as a reaction site in the nucleus. The alkylated phenols can be prepared by well-known methods as, for example, by alkylating phenol or the homologs thereof with an alkyl halide in the presence of a Friedel-Crafts catalyst. Representative alkyl phenols which can be em ployed are those in which the alkyl group contains from 4 to 20 carbon atoms, and preferably those having 8 to 20 carbon atoms such as, for example, n-arnyl phenol, diamyl phenol, octyl phenol, nonyl phenol, p-tert-octyl phenol, a

l (5H1. CH2

The condensation reaction of my invention takes place at temperatures of about 100 to 350 F., preferably at temperatures of about 100 to 270 F., and can be conveniently carried out in the presence of any suitable solvent such as benzene or toluene which can be recovered from the reaction product. out in a mineral oil whereby the condensation product is No special equipment is required for the reaction and any suitable pot type reactor can be employed.

As previously stated, the condensation products" of my invention are characterized as either having reactive phenolic hydroxy groups which remain unsubstituted or which have their hydroxyl hydrogen replaced with an alkaline earth metal compound. The oil-soluble calcium salts are particularly eiiective for'imparting thermal and oxidative stability to mineral oils and can be prepared by neutralization of the condensation product with a basic compound of calcium, such as calcium hydroxide, or by neutralization with a metal oxide or hydroxide followed by preparation of the calcium salt by methathesis. Preferably when If desired, the reaction may be carried.

carrying out the neutralization of the condensation product additional mineral oil of the type employed in preparing a mineral oil concentrate is added to the reaction mixture together with lime and a small amount of water to facilitate the neutralization.

The alkylene polyamines employed in the preparation of the condensation product are represented by the general formula:

in which R is a divalent alkyl radical, substituted or unmixture of phenols, and the like. If desired, the alkylated phenols may also contain one or more substituent groups such as nitro, alkoxy, and the like.

As previously mentioned the inhibitor detergent agents of this invention are employed in lubricating oil compositions which contain basic salts or soaps of oil-soluble sulfonic acids. The basic salts or soaps which are employed are preferably the alkaline earth metal salts of petroleum sulfonic acids, and more particularly the calcium and barium salts. The oil-soluble sulfonic'acids, referred to as mahogany acids, are well known and may be obtained by sulfonating a suitable petroleum distillate with oleum or sulfur trioxide to obtain a 10 to 20 percent concentrate of mahogany acids in the acid oil. The useful mahogany acids generally have a molecular weight of from about 300 to 500, or more, and may be converted into the basic salts by neutralization of the acid oil with an excess of basic barium or calcium compound to obtain basic sulfonates having a higher metal content than the normal salt. Generally, the barium neutralizing agent is reacted with the mahogany acids in a proportion of at least about 1.5 times the theoretical amount required to obtain the normal salt while with calcium the proportion is at least about 1.1. The amount of basic alkaline earth metal sulfonate used in the mineral oil base depends upon the nature of the base stock employed and its service application. Generally, the basic metal sulfonate is used in a range of from about 0.5 percent to 10 percent by weight on a dry soap for example, in solvents such as benzene or toluene, it is preferred to produce the additive by reaction in a solvent refined neutral oil so as to obtain a mineral oil concentrate. The resulting concentrate, either alone or as the alkaline earth metal salt, preferably the calcium salt, may be incorporated in the desired lubricating oil in a small proportion sufficient to impart the desired function of the additive. As detergent-inhibitors, alone or in combination with other additives, the metal salts are usually blended with the oil in an amount to provide a calcium level of about 0.01 to 0.5 percent by weight. As ashless detergents which can be used as such or in combination with other well-known detergents, and which further exhibit oxidation inhibiting properties as we'll as good dispersant properties, the condensation products are usually blended in an amount of about 0.1 to 5.0 percent by weight based on the weight of mineral oil.

The following examples serve to illustrate more clearly the preparation of the condensation products of my invention and the desirable results obtained by their use in mineral oils. 5

Example I 412.6 grams (2 moles) of p-tert-octylphenol, 94.7 grams (0.5 mole) of tetraethylenepentamine and 750 grams of a solvent-treated Mid-Continent neutral oil were placed in a 3-liter, 4-necked flask equipped with a heater, thermometer and Dean Star-k trap. The mixture was heated to about 185 F. and two moles of formalin were added over a period of one hour. The temperature was maintained at 200 to 230 F. for an additional hour and dehydration of the reaction mixture was then effected at 240260 F. under a slight vacuum. The total reaction time was three hours. The product, identified as 58a, was an extremely viscous liquid which was obtained as a 40 percent concentrate in a yield of 98.5 percent of the theo- Forty grams of 58a was blended in 360 grams of a Mid- Continent neutral oil and tested for viscosity and pour point characteristics. The following data were obtained:

KV centistokes:

100 F. 43.8 210 F. 6.21 Pour point F 5 VI 96 Two hundred and twenty-eight grams of product 58:: (40 percent concentrate) and 1 mole of calcium hydroxide containing 80 grams of water were placed in an apparatus similar to that described above. The mixture was heated with stirring to about 300 F. and an additional 322 grams of the Mid-Continent solvent refined neutral oil was added. Heating was continued at 300 F. for about 3 hours until dehydration was complete. One percent by weight of Super-Gel was added to the mixture with stirring and the mixture was filtered hot in vacuo through a heated Buchner funnel. The resulting product (as an 18 percent concentrate) was a clear, amber colored liquid, having the following analysis:

Example 11 In a 5-liter, 4-necked flask, equipped as described in Example I was placed 825.2 grams (4 moles) of p-tertoctylphenol, 1359 grams of a Mid-Continent solvent refined neutral oil and 189 grams (1 mole) of tetraethylenepentamine. The mixing of the above ingredients caused a slight rise in temperature of the reaction mixture. The mixture was heated to about F. and 4 moles of formalin (37 percent) were added over a period of about two hours. The mixture was then heated for three hours while continuouslyincreasing the temperature. At the end of the three-hour period, a maximum temperature of about 345 F. was achieved and dehydration was complete. Theproduct, identified as 580a and prepared as a 44 percent concentrate, was a viscous, light amber colored liquid, and weighed 2080 grams (98 percent yield). Analysis showed the following properties:

Percent nitrogen (found) 2.79 Acid No. pH 11 0.4 Base No. pH 4 71.0

To a mixture of the above product 58aa (1025 grams) and 1000 grams of a Mid-Continent solvent refined neutral oil was added, with stirring, 2 moles of calcium hydroxide and 100 grams of water. The reaction mixture was heated at 230 to 250 F. for two hours, and the temperature was then raised until a maximum temperature of about 330 F. was attained at complete dehydration. The product was filtered hot, in vacuo, employing Super- Cel. The product was a clear amber liquid and was a 22.5 percent concentrate of the calcium salt of product 58cm. Analysis showed the following:

Percent calcium (found) 1.30 Acid No. pH 11 0.00 Base No. pH 4 73.6 Initial pH 11.2

Example III In a 5-liter, 3=necked flask, equipped with a heater, stirrer, thermometer and dropping funnel, was placed 1237.8 grams (6 moles) of p-tert-octyl-phenol and 206.32 grams (2 moles) of diethylenetriamine. The amine was added slowly over a period of 30 minutes to the octylphenol which was heated to about F. The temperature was about F. after the amine addition was completed, and the addition of the formalin (6 moles, 37 percent) was initiated. The formalin was added over a period of one hour and the reaction mixture was heated slowly to about 320 F. until dehydration of the mixture was completed. The hot reaction product, identified as 580 and obtained as 100 percent concentrate, was poured from the reaction flask into a stainless steel beaker where it solidified to an amber colored material. Analysis of the product showed the following properties:

Acid No. pH 11 1.40 Base No. pH 4 132.3 Percent nitrogen (found) 5.38 Initial pH 9.0

The above product 580 was dissolved in a Mid-Continent solvent refined neutral oil and neutralized with calcium hydroxide in the usual manner to give a 34 percent concentration of product 580. The filtered calcium salt Example IV By employing the technique described above for the preparation of product 580, only using a ratio of 2 moles of aldehyde and phenol per mole of amine, a product of low molecular Weight and high nitrogen content is '7 formed, Thus, when 6 moles of p-tert-octylphenol (1236 grams) were condensed with 309.48 grams (3 moles) of diethylenetriamine and 6 moles of formalin, a light amber-colored product, identified as 58d, was obtained .8 147 grams of formalin (37 percent) was added dropwise over a period of 15 minutes, The reaction mixture was then heated to about 200m 300 F. until dehydration was complete. The reaction product was a clear, straw which had the following analysis: colored, viscous liquid, which was converted to the cal- P t ciurn salt by adding 3 moles of calc um hydroxide. 110 i g i g fi i i 7 ml. of water, and 200 grams of a Mid-Continent solvent Base PH 4 6 refined neutral oil. The mixture was heated over a period Initial H of three hours from 190 to 300 F. at which temperature 10 dehydration was complete. Analysis of the condensation 582 grams of product 58d were blended in 882 grams product showed the following: of a Mid-Continent solvent refined neutral oil and heated P t 1 I to 167 F. 5 moles of calcium hydroxide and 100 grams i of water were added to the mixture. The mixture was eicen m roger Acid No, pH 11 1.76 then heated for three hours while slowly increasing the 15 B N H 4 55 5 temperature until dehydration was complete at a .temi p perature of about 306 F. The calcium salt of product Initial PH 58a was obtained as a 41.5 percent concentrate in the The benefits derived from the condensation products Mid-Continent 011 and had the following C ra t rist prepared in accordance with this invention are illustrated percent calcium 286 in the following tables by the tabulated results obtained Percent nitrogen 5 from the Railroad Oxidation Test as applied to the cal- A id NQ H 11 cium salts of the additive agentsas prepared in Examples Base No. pH 4 15'4 7 I, II and III. This test is of low temperature and long Initial pH 11,9 duration and consists of passing 5 liters of oxygen per KV: hour into 300 ml. of oil blend of 285 for 144 hours. 100 F. 3,767.7 Fifty milliliters of makeup oil is added at 48 hours and 210 F. 64.9 96 hours. The test is carried out in the presence of a Pour point F 10 1" x 3" steel back copper lead catalyst.

TABLE 1 Sample number i 8140 p 10232 8143 S196 8197 8199 8200 Base oil:

Percent Coastal l 50 50 5 5 50- 5 50. Percent Mid-Continent 50 50. 50 in so 50. 50. Additives:

Percent basic calcium sulfonate 12 (0.07% 12 (0.07% 12 (0.07% 12 (0.07% 12 (0.07% 12 (0.07%

Ca). a). Ca). Ca). Ca). Ca). Percent Oronite 216 t Percent calcium phenol sulfide (laboratory 3.6 (0.1%

preparation) Ca) Percent calcium salt of 58a, Example I i 8.3C(0.l% Percent calcium salt of 580, Example III- a). 5 0 ([)).l0%

Percent calcium salt of 58cc, Example II 7 Railroad oxidation used oil tests:

Vis./100 F Via/inc, percent Acid number D-974..-

Weight change cat, mg. Tube varnish or sludge. Some1 sludge Catalyst appearance No sludge- No sludge do No sludge.

1 An acid-treated Coastal Oil Blend having a viscosity of about 90 SUS at 210 F. 2 A solvent-refined oil blend. having a viscosity of about 90 SUS at 210 F. 3 Employed as a 12% concentrate and blended to a calcium level of 07% by weight.

4 Calcium phenol sulfide.

Example V i 1 v IntoaiS-liter, 4-nec k ed flask equipped with a heater,

stirrer, Dean Stark trap and dropping funnel was placed 390 grams of nonylphenol and 95 grams of polymerized ethylene imine. Six hundred grams of a Mid-Continent solvent refined neutral oil was added to themixture and Oxidation Tests.

The data in Tabl I above show that the incorporation of calcium additives 58a, 58m and 58c in the oil blends imparted excellent thermal and oxidation stability to blends containing a basic calcium sulfonate detergent. In every case where a calcium additive of this invention was used in an oil blend, a satisfactory railroad oxidation test was obtained. In contradistinction to this behavior, experimental oils formulated with conventional inhibitors such as a calcium phenol sulfide or Oronite 216 (a sulfurized calcium phenate) gave unsatisfactory Railroad The latter blends gave tests characterized especially by highviscosity increases and high acid numbers. A major point of importance was demonstrated by test blend 8197, in which the calcium salt of product 580 was used at a concentration of 0.05 percent calcium, This test blend performed extremely well although it contained one-half of the normal amou t of calcium. Thus, in combination with a basic sulfonate, the calcium additives can be utilized in much lower concentrations than with conventional inhibitors and yet provide superior performance as oxidation inhibitors. Moreover, as shown hereinafter, additional tests which have been carried out with the non-metallic condensation product have shown that in combination with typical prooxidants, extremely good results have been obtained in the Railroad Oxidation Tests;

The following data presented in Table II show the results obtained in tRailroad Oxidation Tests carried out on blends containing a detergent (basic calcium sul fonate) and a supplementary inhibitor together with the calcium additive 58a as prepared in Example I. Similar blends formulated with several different calcium phenol sulfides instead of the calcium salt of product 58a were also tested for comparison.

As shown below, the data obtained again illustrate the superior performance of the additive agent 58a over the two commercial additives above described, even in the presence of a supplementary inhibitor. The addition of a supplementary inhibitor to the blends formulated with calcium 58a and basic. calcium sulfonate impartedv no additional stability to the oil blends (compare Tables I and II). Thus another outstanding feature of the novel calcium additives is their ability to impart cleanliness and stability to lubricating oils without the addition of supplementary inhibitors.

Varnish and sludge rating 97.5. Bearing loss avg. rug/whole bearing 22.2. Color and condition of bearing Colpper colored-- c ean.

USED OIL TESTS. Acid nun1ber 2.66 Pentane insol. .424 Benzene insol. 2.9.0 Insol. resin v .134 Vis. increase at 100 F. "percent" 17.4

C0astalAcid treated coastal oil blends of oils approximately 61 and 75 SUS vie/210: K, respectively.

2 lWIid-ContinentA blend of Mid-Continent solvent treated neutral oil and, bright stockof. 100SUS via/210 F.

3 As prepared in Example I.

As shown in Table III the. new detergent-inhibitor ad.- ditives impart excellent stability and oxidation resistance as indicated by a total varnish and sludge rating of 97.5. As further shown in the data under bearing loss in these tests, which indicates the. amount of bearing. corrosion expressed in milligrams loss in weight of a standard bearing, the novel additives. effectively suppress degradation of the lubricating oil composition and corrosion of bearing metals resulting from oxidation in they presence of the bearing metals under severe service conditions.

Additional tests were carried out to determine. the ability of the novel additives to act as dispersants by maintaining insolubles, etc. in astate of suspension. The additives prepared in Example I, including condensation product 58a and. the calcium salt thereof, both were compared with a basic barium petroleum sulfonate and a commercial detergent designated as compound x; The data were obtained by employing. the Carbon Black Suspension Test, the procedure. for which. is as follows:

TABLE II Sample number 10240 10154 10135 8144 8145 10285 10134 Base oil:

Percent Coastal 50 50. 50. 50 50.- 50.

Percent Mid-Continent 2 50 50 50 50 50 50. 50. Additives:

Percent Oronite 216 3 2. 45 (10% 2.3 (.10%

Ca). Ca). Percent calcium phenol sulfide 4 3 27 .1%

a Percent calcium phenol sulfide (laboratory preparation.

Percent calcium salt of 5811, Example I Percent basic calcium sulfonate 12 12 l2 Percent inhibitor 6 1. 75 2. 5 2. 5 Railroad oxidation used oil tests:

Vis./100 F 826.1 1, 060 l, 101

Vis./inc., percent 43 2 67.. 49. 7'

Acid number D974 5.63 6. 10 7. 66

Initial nH 1.4 1.3-.

PentaneinsoL, percent 2. 707 2. 517 4. 2

Cat. weight change, mg -13.3'. -6. 1 9. 1

Tube varnish or slud e No sludge sludge.

Catalyst appearance do No sludgo 1 See Table I.

2 See Table I.

8 See Table I.

i A commercialcalcium phenol sulfide having an hydroxyl value of 130.7 and asuliur analysis 01' 6.1%. As employed hereirnthls material isneutrallzed with calcium hydroxide to obtain a product having 3.00% calcium, 5.62% sulfur and a Base N 0. pH 4 of 77 8 5 See Table I.

6 A commercial inhibitor (Pinene-PgS phenol-S Cls-alcohol-reactlon product, neutralized with lime).

TABLE III Chevrolet L-4 Engine Test Results Run at 280 F. Crankcase Sump FRESH OIL COMPOSITION 750 Coastal percent by volume 18 1200 Coastal 1 d0 42 100 Mid-C0ntinent 2 d 40 o calcium 58a; 12% basic calcium sulfonate cone.

percent Ca 0.1 VA-RNISH RATING SLUDGE RATING Piston skirt 9.5 Rocker arms Rocker cover 10.0 Rocker cover 1010 Push rod c0ver 10.0 Push rod cover 9.5

Cylinderwall 10.0 Screen 9.5

Crankcase 10.0 Crankcase 9.5

Total 49.5

A given weight of the additive was blended in a mix- 5 ture comprising 25 ml. of a Mid-Continent refined neu- Total 48.0 IV below shows the results of these tests.

' 1 A' commercial dispersant.

excellent dispersant properties as evidenced by a complete m wrong- '11 TABLE IV 7 Carbon Black Suspension Tests Level of Composition of Blend carbon black r after 17 hrs.

at 150 F., ml.

1. Kerosene plus Mid-Continent solvent refined oil blend having a viscosity of about 90 SUS at 210 F 1 2. Basic barium sulfonate blended to 0.96% barium level plus the composition of 1 above 1 1O 3. Compound 1 (2% active ingredient) plus the composition of 1 above 1 4. Calcium salt of Example I blended to 0.28% calcium level plus the composition of 1 above 2 5. Non-metallic condensation product of Example I, 2%

active ingredient plus composition of 1 above l 60 I All carbon black suspended.

As shown by the above data, oil blends containing the calcium salts of the condensation product of Example} are at least equivalent to the commercial dispersantand have superior dispersant properties as compared to blends containing a basic barium sultonate. Also, as further shown, the non-metallic condensation product imparted suspension of all the carbon black.

Additional tests were carried out with the non-metallic condensation products of this invention in combination with'a typical pro-oxidant such as basic bariumsulfonate.

As shown below in Table V the inhibition of oil blends containing a basic detergent and condensation product -58a was extremely good as shown by the difierence in percent viscosity rise between tests 3, 4 and 5.

12 polymerized ethylene imines having a molecular weight of about 30,000 to 40,000 and an alkylene poly-amine of the formula: V

in which R is a divalent alkylene radical containing about 2 to 6 carbon atoms and n is an integer from 1 to 10, said phenol and formaldehyde being reacted with said alkylene polyamine in a ratio of about 0.5 to 2 moles of each of said phenol and formaldehyde for each nitrogen atom present in said polyamine to inhibit oxidation.

2. The lubricating oil composition of claim 1 in which the inhibitor-detergent agent is the calcium salt of said condensation product.

3. The lubricating oil compositionof claim 1 in which the sul-fonate is about 0.5 to 10% of the composition and the condensation product is about 0.1 to 5% of the composition.

4. The lubricating oil composition of claim 1 in which the sulfonate is about 0.5 to 10% of the composition and the condensation product is an alkaline earth metal salt present in an amount to provide about .01 to 0.5% of TBL Y Catalyst 13-974 pH of Percent Composition of Oil Blend 1 weight acid Pentan oxidized vis. Cat, tube and bubblcr 7 change number insol. oil use Solventtreated Mid-Continent Neutral Oil, 160 SUS at 100 F-.. 9. 4 1.7 0. 64 4.1 9.1 N o sludge, no varnish.

. Oil of 1 plus 1% of product 580 of Example I -9. 0 2. 77 0. 176 6. 2 10 Sludge and varnish. Oil of 1 plus basic barium sulionate blended to 0.96% bariurrm.-- ---13]. 31.12 11.32 2. l 660 Heavy sludge and varnish. Oil of 1 plus 1% of product 58a oi Example I and basic barium 8.8 0.19 O. 018 7. 8 1. 7 Clean.

sullonate to 0.96% barium. w a, V Oil of 1 plus 3% of roduot 58a of Example I and basic barium -26. i 0.81 0. 021 7. 2 2. 4 Do.

sulionate to 0.96% arium. I H p p 1 Concentrations of product 5811 are based on the percentage of active ingredients.

I claim:

1. A lubricating oil composition consisting essentially of a mineral lubricating oil containing minor detergent amounts of a basic'alkaline earth'metal petroleum sul fonate and a minor amount'of an oil-soluble inhibitordetergent agent selected from a member of the group con sisting of a condensation product and the alkaline earth 7 metal salts thereof obtained by reacting an alkyl-substituted phenol, in which the alkyl group contains from about 4 to 20 carbon atoms, and formaldehyde with an amine material selected from the group consisting of References Cited in the file of this patent UNITED STATES PATENTS 2,353,491 Oberright July 11, 1944 2,375,222 Grifliin et al. May 8, 1945 2,414,729' Fleming et al. Jan. 21, 1947 2,459,112 Oberright Ian. 11, 1949 2,723,907 Rogers et a1. Nov. 15, 1955 2,725,357 Kluge et al Nov. 29, 1955 2,725,358 Kluge et a1. Nov. 29, 1955 2,736,701 Neif Feb. 28, 1956 

1. A LUBRICATING OIL COMPOSITION CONSISTING ESSENTIALLY OF A MINERAL LUBRICATING OIL CONTAINING MINOR DEGERGENT AMOUNTS OF A BASIC ALKALINE EARTH METAL PETROLEUM SULFONATE AND A MINOR AMOUNT OF AN OIL-SOLUBLE INHIBITORDEGERGENT AGENT SELECTED FROM A MEMBER OF THE GROUP CONSISTING OF A CONDENSATION PRODUCT AND THE ALKAINE EARTH METAL SALTS THEREOF OBTAINED BY REACTING AN ALKYL-SUBSTITUTED PHENOL, IN WHICH THE ALKYL GROUP CONTAINS FROM ABOUT 4 TO 20 CARBON ATOMS, AND FROMALDEHYDE WITH AN AMINE MATERIAL SELECTED FROM THE GROUP CONSISTING OF POLYMERIZED ETHLYLENE IMINES HAVING A MOLECULAR WEIGHT OF ABOUT 30,000 TO 40,000 AND AN ALKYLENE POLYAMINE OF THE FORMULA: 